The present invention generally relates to oil coolers and, more particularly, apparatus and methods for increasing heat transfer when the oil cooler is hot.
Oil cooler fins can be of a turbulating type to provide maximum heat transfer when hot. However, when cold, the oil does not require cooling and the high viscosity creates high pressure drop when flowing through a highly turbulated fin surface.
To mitigate this problem, oil coolers often have a bypass line at low oil temperatures. This adds cost and complexity to the system, since an actuator and a control are needed.
As can be seen, there is a need for improved apparatus and methods for increased heat transfer in oil coolers having turbulated fins.